It can be appreciated that bone saws and devices such as burrs have been in use for many years. Typically bone saws are comprised of oscillating or reciprocating thin metallic blades driven by portable hand units powered by compressed gas or battery operated.
The main problem with conventional saws and burrs is the excessive wandering of the tip of the blades during the oscillatory cycle, which can cause cutting, shredding or extensive contusions to the surrounding tissues. This issue becomes critical when maneuvering the conventional blades and burrs in very tight spaces. Another problem with conventional small blades is the fact that it is very hard to manually control the tip of the oscillating blade by hand since it is common for the tip to wander and “kick back” in a manner similar to tree chainsaws. In addition, the conventional thin saw blade have tendency to bend when cutting deeply into bone thereby causing a significant error in the cutting process. Another problem with the conventional saw blades is the fact that the bone debris generated from the cutting process are usually disseminated in the wound and further deeply spread into the wound by the irrigation process. The prior art teaches devices that provide irrigation channels that inject fluid into a wound (e.g., U.S. Pat. No. 4,008,720 to Brinkmann et al. and U.S. Pat. No. 5,122,142 to John Pascaloff). However these patents fail to provide a suction channel for removal of bone and tissue debris.
While these devices may be suitable for a particular purpose to which they address, they are not suitable for removing large amount of bone and articular surface including cartilage, more specifically from the knee joint but can be adapted for usage with any large articular surface or other bony structure through a small incision using minimal surgical approach. The main problem with the conventional bone saws and burrs is the excessive excursion of the tip of the cutting blade or bur during the oscillatory cycle is excessive and can cause cutting, shredding or extensive contusions of the surrounding tissues adjacent to the operated surface. This becomes critical when maneuvering these conventional devices in very tight anatomical spaces or through small surgical incisions.
In these respects, the electromagnetic oscillating bone chipper and saw according to the present invention substantially departs from the conventional concepts and design of the prior art, and in so doing provides an apparatus primarily developed for the purpose of removing large amount of bone and articular surface including cartilage and soft tissue mainly from the knee joint but can be adapted for use with any large articular surface through a small incision using minimal surgical approach. Furthermore, the presence of a suction channel allow the removal of bone debris generated by the cutting process.